Kosmina said as the matter sat with the FFA and ASADA, the club would not be able to comment further.

"Nevertheless, Adelaide United recognises the significance of the matter and wants to ensure our members, fans, and stakeholders that we will treat this with the utmost seriousness and sensitivity," he said.

"We ask that commentary on this situation also shows sensitivity to the issues involved."

Coach contract won't be renewed

The incident came as Adelaide United confirmed this week it would not renew German coach Marco Kurz's contract beyond this season.

Chairman Piet van der Pol said the club was grateful for Kurz's hard work and for helping to guide the side to its second FFA Cup trophy.

"Marco has our full support for the remaining games this season as we push to secure a home final and look to go as far as we can in the finals," he said.

"In the coming weeks we will be identifying potential candidates and will not be making further comment on this matter until an appropriate time."

Adelaide United is coming off a 2-0 loss to Perth Glory at Hindmarsh Stadium in Adelaide last weekend and will face Central Coast Mariners this Sunday.

The Reds sit sixth on the A-League table with five games remaining before the finals series.